Self-reported health impacts of the 2010 Hainan Typhoon, China, and the effect of age and ethnicity

Background: Few published studies have examined the health impacts of floods, especially in middle-income countries such as China, and the effects of ethnicity and older age have not been explored. In October 2010, Hainan Island in China experienced severe flooding following heavy rainfall. This study describes the physical and mental health impacts of the floods and investigates differences between age and ethnic groups. Methods: A cross-sectional survey of 267 households was conducted three months after the flooding. A four-stage cluster sampling method was used to randomly select households from affected areas. Information was collected on socio-demographic status, pre-disaster health and experience of the disaster. Results: The incidence of self-reported flood-related physical illness was 22.8%. The most common illnesses were respiratory infections, diarrhea and skin disease. 7.1% reported sustaining an injury. Han Chinese were more likely to report a physical illness/injury than Li ethnic minority (OR=2.4; 95% CI: 1.17-4.88). There was no significant difference in reported physical illness/injury between those <50 years old and those ³50. The Li minority had higher psychological distress levels than Han Chinese (average K6 Scale scores: 23.6 vs. 21.6, p<0.001). There was no significant difference in distress levels between age groups. Female gender (p<0.001), Li ethnicity (p=0.003) and living in a severely affected area (p=0.001) were all independently associated with higher distress levels. Conclusions: The post-flooding morbidity rates reported from this rural, poor area of China are similar to those previously reported from countries including France and Bangladesh. Common causes of morbidity were also similar. Age was not associated with adverse health impacts but ethnicity was: Han Chinese were more likely to report physical illness while the Li minority experienced more psychological distress and worry about safety. These findings can be used to plan targeted disaster preparedness and response activities in such communities in China.